A latest video compression technique, commonly referred to as an H.264/Advanced Video Coding recommendation (International Telecommunication Union-Telecommunication Standardization Sector, Geneva, Switzerland) and/or an MPEG-4 Part 10 recommendation (document ISO/IEC 14496-10 International Organization for Standardization/International Electrotechnical Commission, Geneva, Switzerland) has a better coding efficiency for intra predictions compared with previous video coding standards. The intra prediction coding efficiency is achieved by an extensive use of spatial context to derive a prediction. Intra-coded macroblocks are predicted either as 16×16 sample blocks, 8×8 sample blocks or 4×4 sample blocks. The 4×4 sample prediction mode is better suited for areas that have many spatial details.
Referring to FIG. 1, a diagram of an H.264/AVC intra 4×4 luminance order sequence 90 is shown. A luminance component of a macroblock is partitioned in four 8×8 sample blocks and each of the 8×8 sample blocks is further partitioned in four 4×4 sample blocks. The 4×4 sample blocks are coded using the order 90 from a position 0 to a position 15 sequentially. A prediction of each 4×4 sample block is based on the samples in the spatial neighbors. The dependencies between spatial neighbors impose a limit of how far the intra 4×4 encoding and decoding can be parallelized.